Device and methods of inspecting soldered connections

ABSTRACT

A device for inspecting solder connections between a component and a substrate or between two components or substrates, wherein the component is disposed upon the surface of the substrate, the device including an image receiving unit. An image transmitting device, the image transmitting device including a first end and a second end, the first end coupled to the image receiving unit. A tip assembly removably coupled to the second end of the image transmitting device, the tip assembly further including a mirror and an image receiving aperture, the tip assembly configured to transmit an image of the solder connections received by the mirror, through the image transmitting device, to the image receiving unit, and an illumination device, the illumination device including a light source, at least one light transmitting device, and at least one light emitting aperture disposed adjacent the image receiving aperture, the light emitting aperture directed towards the solder connections to be inspected.

TECHNICAL FIELD

[0001] The present invention relates to devices and methods forinspecting soldered connections, more particularly the device of thepresent invention allows for visually inspecting concealed solderedconnections such as those utilized to attach an integrated circuit to aprinted circuit board.

BACKGROUND OF THE INVENTION

[0002] With the advances in technology related to integrated circuits(ICs) and in particular to surface mount IC's and more particular toball grid arrays (BGAs) and chip scale packages (CSPS) and flip chips(FCs) in addition to the density of ICs utilized in electronics devicesit has become increasingly difficult to visually inspect the integrityof the soldered connection between the chip leads and the solder pads ona printed circuit board. In addition, the number of soldered connectionsper chip has increased while inversely the size of the chip hasdecreased. While some surface mounted ICs have soldered connectionswhich can be visually inspected because the chip leads project from theedge of the IC, the above-referenced chips cannot be visually inspectedwithout an inspection device because the chip leads projectperpendicular to the surface of the IC, and therefore the solderedconnections are hidden by the IC.

[0003] One method to test the integrity of a soldered connection is thatshown in U.S. Pat. No. 6,288,346 Hirofumi et al. wherein a plurality oftest lands are disposed upon the circuit board which are connected tosolder pads to which a BGA package is to be soldered to in which thecontinuity between the pins on the BGA can be confirmed. While thisinspection method may disclose an open connection it cannot distinguishif there is a ‘bridged-connection’ that is where a ball of solderconnects more than one pin. A bridged connection may lead to componentfailure when power is applied to the IC, therefore it is desirable todetermine if bridged connections exist. Additionally, the testing methodof Hirofumi et al. does not disclose the quality of the solderedconnections, that is whether the solder was not heated to a high enoughtemperature. Therefore, the expected lifetime of the soldered connectioncannot be estimated which may lead to more product failure after sales.

[0004] Another method to check soldered connections for theabove-referenced IC's is through the use of x-rays. With x-rayinspection, it can be determined whether there are open connections,bridged connections and if the BGA was properly aligned with the solderpads of the printed circuit board. It is not possible to determine thequality of the soldered joint, as described above. In addition, itcannot be determined if excess flux residue remains within the solderedconnections. Still further, the use of x-ray inspection requiresdedicated equipment in addition to requiring protection from radiationexposure from the x-ray testing device. Lastly, x-ray inspection unitsrequire a skilled operator to utilize the device, thereby leading tocomplexity as well as costs to the overall product.

[0005] Still yet another method of inspection that is known is theproduction of a micrograph in cross-section through a solderedconnection. This requires destructive testing, wherein a circuit boardis taken from the assembly line and a cut is made passing through the ICto visually inspect the soldered connection. Though, this method willonly produce an estimate of the actual soldered connections and requiresthat conclusions must be drawn as to the operating parameters of thesoldering process.

[0006] Another known process of inspecting soldered connections isthrough the use of devices which can transmit images from one locationto another, such devices include endoscopes and borescopes. Thesedevices generally have a cylindrical profile and include a plurality oflenses disposed therein for the transmission of an image therethrough. Ashortcoming of these devices is that at one end of the device there isdisposed a light source adjacent to an image collection device. Thelight source is utilized to illuminate the area adjacent to the imagecollection device wherein an image is then reflected into the endoscopeand transmitted to the opposite end. The clarity of the transmittedimage may be diluted due to excess light emitted and/or reflected fromthe light source which is transmitted through the device.

[0007] Referring now to U.S. Patent Application Publication No.2001/0024273 Cannon, there is disclosed yet another device for theinspection of soldered connections. In particular, the inspection deviceshown and described in the above-referenced patent application can beutilized to visually inspect soldered connections of BGA, CSPS, and FCs.The device includes an ocular unit, a lens head, and image transmissionunit for transmitting the image receive by the lens head to the ocularunit and an illuminating device. As shown and described in Cannon thedevice therein may be utilized by placing the lens head adjacent to aBGA to be inspected. An illumination source illuminates the solderedconnections while a second illumination source is utilized to backlightthe soldered connections. A prism assembly disposed within the lens headreceives a reflected image of the soldered connections, the reflectedimage is transmitted through an image transmission unit and into acamera. An aperture is disposed between the transmission unit and thecamera to control the image received by the camera. A shortcoming of thedevice of Cannon is that the image reflected through the imagetransmission unit contains “interference” which leads to the degradationof the image. The term “interference” refers to the excess reflectedlight which will be transmitted through the image transmission unit.This excess light will combine with the image to be view, wherein thefinal combination of the image to be viewed and the interference willthen be filtered by the aperture disposed adjacent the camera. Anadditional shortcoming of the device of Cannon is that the field of viewof the lens head is to narrow to visually inspect both the upper solderconnections as well as the lower solder connections, in order tovisually inspect both, the lens head must be moved away from thesoldered connections to provided a greater field of view, though at thecost of clarity of the image. A further shortcoming of the Cannon deviceis that a prism is utilized to reflect the image of the solderedconnections, it is well known that prisms tend to be brittle andtherefore require protection. For example, as shown in Cannon the prismis protected by webs, these webs extend beyond the edge of the prism,therefore the leading edge of the prism cannot be lowered such that theprism contacts the circuit board because of the protection webs. Lastly,prisms are very expensive therefore increasing the overall cost of theinspection device, as well as requiring specially trained techniciansfor repairs and/or servicing of the prism assembly.

[0008] Therefore there is a need for a device and methods of use whichwill enable the visual inspection of soldered connections, wherein thedevice provides a clear image of both the upper and lower connectionwithout having to readjust the focal length of the device. Additionally,there is a need for an optical inspection device that eliminatesinterference within the transmitted image, thereby providing a betterimage of the soldered connection.

SUMMARY OF THE INVENTION

[0009] In accordance with the present invention there is provided adevice for inspecting solder connections between a component and asubstrate or between two components or substrates, the device includesan image receiving unit, an image transmitting device, including a firstend and a second end, the first end coupled to the image receiving unit.A tip assembly removably coupled to the second end of the imagetransmitting device, the tip assembly further including a reflectivedevice and an image receiving aperture, the tip assembly configured totransmit an image of the solder connections received by the reflectivedevice, through the image transmitting device, to the image receivingunit, and an illumination device, including a light source, at least onelight transmitting device, and at least one light emitting aperturedisposed adjacent the image receiving aperture, the light emittingaperture directed towards the solder connections to be inspected.

[0010] In accordance with the present invention there is provided adevice for optically inspecting soldered connections, the deviceincluding, a camera, and an image transmitting device. The imagetransmitting device including a generally circular cross-sectionalprofile first end and a second end and a bore extending therethrough,the first end coupled to the camera, and a at least one imagetransmitting lens disposed within the bore. A tip assembly removablycoupled to the second end of the transmitting device. The tip assemblyfurther including a mirror and an image receiving aperture disposedadjacent to the mirror, the image receiving aperture and the mirrorconfigured to receive and transmit an image the soldered connections tothe camera through the image transmitting device, and at least oneillumination device, the illumination device comprising a light source,a device for transmitting light from the light source to a lighttransmitting aperture disposed within the tip assembly, the lighttransmitting aperture disposed adjacent to the image receiving aperture.

[0011] In accordance with the present invention there is provided amethod of inspecting soldered connections between an IC and a circuitboard, the method including the steps of disposing a circuit boardhaving at least one IC soldered thereto on a work surface of aninspection device. Aligning a tip of the inspection device with a row ofsoldered connections to be inspected. Using an optical inspection deviceto view the soldered connections between the IC and the circuit board,the optical inspection device including a camera, an image transmittingdevice comprising a generally cylindrical member having a first andsecond end the first end coupled to said camera, and a removable tipassembly coupled to the second end of the image transmitting device, theremovable tip assembly including a main body housing at least one lighttransmitting aperture and a reflective device and an image receivingaperture disposed adjacent to the light transmitting aperture, the lighttransmitting aperture and image receiving aperture directed toward thesoldered connections to be inspected, the reflective device adapted toreceive and transmit and image of the soldered connections to thecamera. Illuminating the soldered connections to be inspected, andvisually examining the soldered connections between the IC and thecircuit board by pivoting the camera, image transmitting device, and tipassembly about an optical centerline of the reflective device to viewthe upper or lower solder connections and rotating the camera, imagetransmitting device, and the tip assembly through about 90 degrees toview the sides of the soldered connections. Moving the IC relative tothe tip assembly to visually inspect other soldered connections betweenthe IC and the circuit board, and visually inspecting the gaps formedbetween the soldered connections for optical clarity.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In the drawings, wherein like numbers have be utilized to denotethe same or similar parts:

[0013]FIG. 1. is a perspective view of the inspection device accordingto the present invention;

[0014]FIG. 2. is a front view of the optical inspection unit of theinspection device according to an exemplary embodiment of the presentinvention;

[0015]FIG. 3. is a back view of the optical inspection unit of theinspection device according to an exemplary embodiment of the presentinvention illustrating the pivoting mechanism in accordance with thepresent invention;

[0016]FIG. 4. is an isometric view of the tip assembly in accordance toan exemplary embodiment of the present invention;

[0017]FIG. 5. is a partial side view of the tip assembly and tipassembly holder in accordance to an exemplary embodiment of the presentinvention; and

[0018]FIG. 6. is an isometric view of the tip assembly illustrating themirror disposed within the tip assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] The present invention comprises a test device for inspectingsolder connections between a substrate and an integrated circuit. Thetest device includes a base assembly and an optical inspection unitconnected to the base. The base further including a substantiallyhorizontal work area wherein a component to be inspected in placed. Theoptical inspection unit may be moved vertically and rotatable withrespect to the work area.

[0020] Referring now to FIG. 1 there is shown the testing device 10 inaccordance with the present invention. The testing device 10 includes abase assembly 20, and an optical inspection unit 100. The base assembly20 further comprises a horizontal work surface 30, wherein thehorizontal work surface 30 can be moved in both a vertical andhorizontal plane relative to the optical inspection unit 100.

[0021] The work surface 30 may be displaced by rotating the knobs 31 and32, the knobs 31 and 32 being operatively coupled to the work surface 30utilizing known mechanical means. Alternatively, the work surface 30 maybe coupled to an electrical drive system, wherein the knobs 31 and 32control electrical switches which power drive motors coupled to the worksurface.

[0022] As shown in FIG. 1, the base assembly 20 further includes avertical member 15 fixedly attached thereto and protruding perpendicularto the work surface 30. The vertical member 15 is further configured toreceive arm 18, wherein arm 18 may be coupled to vertical member 15through a gear drive assembly, the gear drive assembly controlled byknobs 17 whereby the knobs 17 may be utilized to control the height ofthe arm 18 relative to the work surface 30. It shall be understood thatthe use of a gear driven assembly to control the height of arm 18 ismerely exemplary and should not be considered limiting in any manner. Itis contemplated that many different mechanical, electromechanical,electrical, and hydraulic systems may be utilized to control the heightof arm 18 relative to the work surface 30. Additionally, the controlmeans 17 may further include a locking means, thereby enabling a user tofix the height of the arm 18 relative to the work surface 30.

[0023] The arm 18 further includes receiving means adapted to receive anoptical inspection unit 100 as shown in FIG. 1. Additionally, as shown,the testing device 10 may further include a second illumination device40 configured to provide additional illumination to the solderedconnections to be viewed. The second illumination device includes a tip41, a flexible shaft 44, and a device for transmitting light 45. Thedevice for transmitting light may include at least one LED disposedwithin the tip 41. Preferably, the device for transmitting lightcomprises a light pipe or fiber optic device, wherein one end isconnected to a light source and the other end is configured to emitlight from the tip 41, the tip 41 may further include a prism or mirrorto reflect light in a desired direction. The light source may be thesame source for use with the illumination device disposed within the tipassembly as will be described in detail below, or it may be a secondsource. Additionally, the second illumination device is configured to bemoved independently of the movement of the inspection unit 100, therebyenabling a user to place the second illumination device at any desiredposition and height.

[0024] Referring now to FIG. 2, there is shown an exemplary embodimentof the optical inspection unit 100 in accordance with the presentinvention. As shown in FIG. 2, the optical inspection unit 100 comprisesa coupling device 101, a rotating assembly 200, a focusing assembly 162,an image transmitting device 160 and a tip assembly 150.

[0025] The coupling device 101 is adapted to be received with the frame18 wherein the coupling device retains the optical inspection unit 100within the frame 18. The coupling may be fixedly received within the arm18 or alternatively the coupling 101 may be rotatably received withinthe arm 18, thereby allowing the optical inspection unit 100 to berotated relative to the arm 18 and the work surface 30.

[0026] The rotating assembly 200 includes the rotating knob 102 and agear drive unit (not shown) and a pivot plate 111 as shown in FIG. 3.The pivot plate 111 further includes a groove 112 and a pin 115 disposedwithin the groove. Referring now to FIGS. 1, 2, and 3, it can be seenthat rotating knob 102 projects from a groove formed within arm 18.Displacing the rotating knob 102 within the groove acts upon a geardrive assembly coupled to the camera, the focusing unit, the imagetransmitting device 160, and the tip assembly 150, thereby rotating theassembly clockwise and counterclockwise relative to an axisperpendicular to the work surface 30. In addition to the above, theoptical inspection unit 100 may further be pivoted about the opticalcenterline of the reflective device disposed within the tip assembly.The optical inspection unit may be pivoted by rotating the rotating knob102 clockwise or counter clockwise. The pivoting assembly can be betterunderstood with reference to FIG. 3, where there is shown the pivotplate 111, the pivot plate including a groove 112 disposed therein and apin 115 disposed within the groove 112. In use, the pivot plate 111 isfixedly attached to the coupling device 101 which is attached to the arm18, thus allowing the optical inspection unit to pivot relative to thevertical support member 15. By pivoting the optical inspection unit 100about the optical centerline of the reflective device disposed withinthe tip assembly allows for the inspection of both the top solderedconnections as well as the bottom soldered connections without having tochange the focal length of the reflective device relative to thesoldered connections. The optical inspection unit pivots through onangle of P, the angle P can be between about 0 and about 180 degrees,preferably between about 0 and about 45 degrees, more preferably betweenabout 0 and about 10 degrees, and most preferably between about 0 andabout 5 degrees. It shall be understood that the assembly maybe pivotedabout either side of an axis perpendicular to the work surface 30.

[0027] As shown in FIGS. 2 and 3 the optical inspection unit 100includes a focusing device 162. The focusing device is operativelycoupled to the camera 200 and the image transmission unit 160, whereinthe focusing device 162 may further include a plurality of lenses,whereby the focal length of the lens may be adjusted by rotating thefocusing assembly. Additionally, the focusing assembly may be utilizedto adjust the sharpness of the image. It shall be understood that thefocusing assembly as described herein and as utilized within the presentinvention does not include an aperture. The camera 200 may be aconventional film camera, more preferably the camera 200 is a digitalcamera such as a CCD camera or similar electronic cameras which providea video output that may be displayed on a conventional display such as acathode ray tube CRT device or a liquid crystal display LCD device.

[0028] Referring now FIGS. 2 and 3, there is shown an exemplaryembodiment of the image transmission unit 160 in accordance with thepresent invention. The image transmission unit 160 comprises a generallycylindrical body having a first end and a second end, the first endbeing coupled to the focusing assembly 162, the second end being adaptedto receive the tip assembly 150. The image transmission unit 160 mayfurther include a plurality of lenses disposed therein. The generallycylindrical body may be constructed of a rigid material or of a flexiblematerial. Additionally, as shown in FIGS. 1 and 2 a plurality of lighttransmitting elements 173 may be disposed upon the image transmissionunit. The light transmitting elements may be fiber optic bundles,polished hollow cylindrical tubes, or other devices which may beutilized to transmit light. In a preferred embodiment the lighttransmitting elements are fiber optics which may comprise one or moreelements. The light transmitting devices include a first end and asecond end, the first end coupled to a light source (not shown) and thesecond end configured to be received within the tip assembly 150. Thelight source may comprise a conventional monofilament bulb, morepreferably the light source is a metal halide lamp. Alternatively, it iscontemplated that other sources of illumination may be utilized. In analternative embodiment (not shown) it is contemplated that lightemitting diodes (LED) may be disposed within the tip assembly 150thereby eliminating the need for the light transmitting elements,wherein the light transmitting elements would be replaced with powercords for powering the LED's installed in the tip assembly.

[0029] Referring not to FIG. 4 there is shown a exemplary embodiment ofthe tip assembly 150 in accordance with the present invention. The tipassembly 150 includes a main body 159, at least one light transmittingaperture 155, a mirror, prism or similar reflective device, and an imagereceiving aperture 156 formed within the housing, wherein the imagereceiving aperture 156 is formed having a pre-determined diameter whichhas been chosen to improve the quality of the image to be received bythe camera. This is unlike conventional inspection devices wherein theaperture is placed adjacent to the camera assembly, by placing theaperture of the camera assembly before the reflective device reduces theamount of light pollution transmitted to the camera for magnification.

[0030] The main housing 159 may be formed of metal or plastic or anycombination thereof. In a preferred embodiment, the main housing 159 isformed of plastic. The main housing 159 may be formed of multiple pieceswhich are assembled together, or alternatively, the main housing may beformed of a unitary body wherein the mirror or reflective element is hasbeen molded therein.

[0031] Referring now to FIG. 6, it can be seen that the reflectivedevice 154 is disposed within the lower portion of the main housing 159such that light transmitted through the apertures 153 will be reflectedby the reflective device in the direction of the soldered connections tobe viewed. Additionally, as shown in FIG. 6, it can be seen that theimage receiving aperture 156 is disposed between the solderedconnections to be viewed and the reflective device 154. By placing theimage receiving aperture 156 between the soldered connection to beviewed and the reflective device 154 a sharper and clearer image istransmitted to the camera assembly for magnification as described indetail in another section of the current application.

[0032] Referring now to FIG. 4 it can be seen that the main body 159further includes a reduced thickness region 157 as shown. The reducedthickness region 157 enables the tip assembly to be constructed having alower profile, and therefore require less room between IC's installed ona circuit board. Furthermore, as shown in FIG. 6, the leading edge ofthe reflective device can be placed very near to the lower edge of thereduced thickness region 157, thereby enabling the reflective device tobe placed closer to the work surface 30 or closer to a circuit board,thereby enabling lower profile assemblies to be inspected.

[0033] The main housing 159 further includes at least one light emittingaperture 155 formed therein, wherein the light emitting aperture isconfigured to utilize the reflective device to reflect light in thedirection of the soldered connections to be viewed. In a preferredembodiment, the main housing includes two separate light emittingapertures 155 as shown in FIG. 4. The benefit of utilizing two separatelight emitting apertures will become apparent following the discussionbelow regarding the image receiving aperture 156.

[0034] As described above, the tip assembly includes a image receivingaperture 156 disposed adjacent the distal end of the reduced thicknesssection 157. The image receiving aperture 156 is operatively coupled tothe mirror and the image transmission aperture 158 formed within themain body 159 of the tip assembly. The image receiving aperture 156replaces a conventional (camera) aperture which may be disposed withinthe lens assembly of the camera or within the camera body. Forming theimage receiving aperture 156 into the tip assembly provides manybenefits over conventional style inspection devices wherein the apertureis disposed adjacent the camera. A primary benefit that is provided, isthat the image receiving aperture 156 acts as a filter to block excesslight from the light source(s) from being transmitted to the camera.

[0035] In a conventional inspection device, because the aperture ismounted adjacent the camera, the reflected image as well as excess lightfrom illumination sources is transmitted to the camera assembly, theexcess light causes interference in the image quality and degrades theoverall image. This degradation of the image means that eitherpost-processing of the image must occur in order to clarify the image,or alternatively excessive magnification must be utilized to provide aclear image. Therefore, as described above the image receiving aperture156 filters excessive light from the image to be viewed. Unlike aconventional optical aperture disposed within a camera lens or camerabody, the image receiving aperture according to the present invention isformed having a pre-determined diameter, that is the image receivingaperture 156 is non-adjustable, unlike conventional photographicapertures. Though it is contemplated that an adjustable aperture couldbe fabricated wherein the tip assembly further includes a removableportion, wherein the removable portion includes the image receivingaperture, therefore to adjust the aperture size, removable portionscould be substituted. Alternatively, the image receiving aperture 156could be fabricated to comprise a conventional mechanical aperture.

[0036] Referring now to FIG. 6, there is shown a cross-sectional sideview of the tip assembly according to the present invention. As shown inFIG. 6, the tip assembly 150, reflective device 154 is disposed withinthe reduced thickness section 157. As shown, the image receivingaperture 156 is disposed optically in front of the reflective device154.

[0037] In addition to the advantages described above by placing theaperture on the tip assembly in the manner shown and described allowsthe use of a image transmitting unit 160 to extend the distance betweenthe tip assembly and the camera assembly. This is not possible withother inspection devices that utilize a reflected image and an aperturemounted on a camera because the image degradation is to great over largedistances as well as the increase in noise introduced to the image asdescribed above.

[0038] Referring now to FIG. 5, there is shown the tip assembly 150 andthe tip carrier 169. The tip carrier comprises a main body 170 disposedupon the first end of the image transmitting unit 160. The main body 170of the tip carrier is configured to receive the light transmittingdevices 173 disposed upon the image transmitting unit 160. Stillfurther, the main body is further adapted to removably receive the tipassembly 150 as shown. Referring now to FIG. 4 it can be seen that themain body 150 of the tip assembly 150 is adapted to slidably receive thelight transmitting devices within channels 153 formed in the main body.Additionally, as shown the channels 153 are separated from the imagetransmission aperture, thereby forming an enclosed optical path betweenthe image transmitting aperture and the image receiving aperture 156.

[0039] It is contemplated that different tip assemblies could befabricated which can be disposed within the tip carrier 169. That is tipassemblies having larger or smaller apertures to control the qualityand/or size of the image. In addition, during an inspection process thetip may contact the integrated circuit being inspected. If this were tohappen, many times the tip is damaged or destroyed, in a conventionalinspection device this would require a skilled technician to performservice on the device. The present invention allows for anyone to easilyreplace the tip without requiring complex service steps. That is, thedamaged tip could be removed from the first end of the imagetransmission device, discarded and then a new tip couple be slid andlocked into place. This provides the benefit of not requiring a servicecall, and further reduces the down time of the inspection device due torepairs. Another improvement of the present invention over conventionalinspection devices is that if the mirror disposed within the tipassembly becomes dirty due to contamination or for any other reason itmay be easily and inexpensively replaced.

[0040] Referring now to FIGS. 1-6 the use of the inspection deviceaccording to the present invention will be described. In use, a circuitboard containing at least one IC having been soldered thereto is placedwithin the work surface 30. The inspection device 100 is moved intoposition such that the image receiving aperture 156 is disposed to viewthe soldered connections of the IC. It is contemplated that the worksurface 30 may be moved relative to the inspection device 100 or thecircuit board may be moved or further still the inspection device 100may be moved or any combination of the above may be moved. After theimage receiving aperture 156 is disposed within a position to view thesoldered connections an image is displayed on a display device (notshown) such as a monitor, LCD panel, television, or similar devices.After, viewing the soldered connections, the rotating knob may berotated clockwise or counterclockwise to pivot the inspection device100. By pivoting the inspection device this will allow the imagereceiving aperture to receive an image of either the top solderedconnections or the bottom soldered connections without requiring theinspection unit to be moved relative to the IC to be inspected, unlikeconventional inspection devices which must be moved away from the IC inorder to expand the field of view which results in a loss of imageclarity. After the upper and lower soldered connections have beenviewed, the rotating knob may be rotated within the groove disposed inthe arm 18, thereby directing the image receiving aperture 156 to viewother rows of soldered connections or to view the soldered connectionsat a different angle. Throughout the procedure described above, light isemitted from the apertures 155 of the tip assembly to illuminate thesoldered connections to be viewed. Additionally, the second illuminationdevice may be disposed on the side opposite to the tip assembly toprovide backlighting of the soldered connections, or in any otherposition to provided desired lighting. As shown in FIG. 1, the secondillumination source, in a preferred embodiment, may be movedindependently relative to the tip assembly 150, though it iscontemplated that the second light source may be coupled to the movementof the imaging device 100 such that less user intervention is needed toprovide the necessary lighting. By providing a second illuminationdevice which may be moved independent of the imaging device 100 allowsthe inspection device 10 according to the present invention to beutilized to inspect ICs that may have heat sinks or similar devicescoupled thereto because the inspection device 100 and the secondillumination device 40 may be moved independently about the IC to beinspected.

[0041] It shall be understood that the examples described herein andshown in the appended figures are exemplary and should not be consideredlimiting in any manner. It is contemplated that one skilled in the artmay undertake modifications to the present invention without deviatingfrom the scope of the invention.

What is claimed is:
 1. A device for inspecting solder connectionsbetween a component and a substrate or between two components orsubstrates, the device comprising: an image receiving unit; an imagetransmitting device, including a first end and a second end, the firstend coupled to said image receiving unit; a tip assembly removablycoupled to said second end of said image transmitting device, said tipassembly further including a reflective device and an image receivingaperture, the tip assembly configured to transmit an image of saidsolder connections received by said reflective device, through saidimage transmitting device, to said image receiving unit; and anillumination device including at least one light emitting aperturedisposed adjacent said image receiving aperture, said light emittingaperture directed towards said solder connections to be inspected. 2.The device according to claim 1, wherein the image receiving unitcomprises a camera.
 3. The device according to claim 2, wherein theimage transmitting device includes a generally cylindrical body having aplurality of lenses disposed therein.
 4. The device according to claim1, wherein the image receiving unit includes a lens assembly coupledthereto, said lens assembly capable of increasing or decreasingmagnification of said image to be received therein.
 5. The deviceaccording to claim 1, wherein said illumination device includes lightsource and a device for transmitting light from the light source to thelight emitting aperture.
 6. The device according to claim 1, whereinsaid image receiving unit is disposed within a housing, said housingpivotally attached to a frame.
 7. The device according to claim 6,wherein a pivot point of rotation of said housing is the opticalcenterline of said mirror disposed within the tip assembly.
 8. Thedevice according to claim 7, wherein said image transmitting device andsaid tip assembly are rotatable about an axis perpendicular to saidsubstrate.
 9. The device according to claim 1, wherein said aperturefilters the image to be transmitted prior to transmission of the imageby the image transmitting device.
 10. The device according to claim 1,further including a display device coupled to said image receiving unit,the display device configured to display the solder connections to beinspected.
 11. The device according to claim 1, wherein said tipassembly further includes an illumination aperture disposed on eitherside of said image receiving aperture, wherein said illuminationapertures direct light onto said solder connections to be inspected. 12.The device according to claim 6, wherein said angle of pivot is betweenabout 0 and about 5 degrees.
 13. The device according to claim 1,further including a back lighting assembly, the back lighting includingan illumination source, a lens assembly, and a flexible arm coupledthereto.
 14. The device according to claim 5, wherein said device fortransmitting light is a fiber optic device.
 15. The device according toclaim 1, wherein the illumination device includes a light emitting diodedisposed within said light emitting aperture and a power source coupledto said light emitting diode.
 16. A device for optically inspectingsoldered connections, the device comprising: a camera; a imagetransmitting device, including a generally circular cross-sectionalprofile first end and a second end and a bore extending therethrough,said first end coupled to the camera, and a at least one imagetransmitting lens disposed within the bore; a tip assembly removablycoupled to said second end of said transmitting device, said tipassembly further including a mirror and an image receiving aperturedisposed adjacent to said mirror, said image receiving aperture and saidmirror configured to receive and transmit an image the solderedconnections to said camera through said image transmitting device; andat least one illumination device, the illumination device comprising alight source, a device for transmitting light from the light source to alight transmitting aperture disposed within said tip assembly, the lighttransmitting aperture disposed adjacent to the image receiving aperture.17. The device according to claim 16, further including a magnifyinglens disposed between the camera and the first end of the imagetransmitting device, the magnifying lens capable if magnifying the imageof the soldered connection.
 18. The device according to claim 16,wherein said camera, image transmitting device, and tip assembly arerotatably and pivotally coupled to a movable arm, the movable armcoupled to a frame, the frame including a work surface configured toreceive a circuit board to be inspected, the camera, image transmittingdevice and tip assembly being disposed generally perpendicular to saidwork surface.
 19. The device according to claim 18, wherein the camera,image transmitting device, and tip assembly are pivotable between about−10 and about 10 degrees relative to an axis extending perpendicularfrom said work surface.
 20. The device according to claim 19, whereinthe camera, image transmitting device, and tip assembly may be rotatedabout said perpendicular axis.
 21. The device according to claim 20,further including a second illumination device, the second illuminationdevice comprising a flexible shaft extending from said arm and a tipassembly, the tip assembly including a light transmitting aperture,wherein a light transmitting device is connected at one end to a lightsource and at the other end to the light transmitting aperture, thesecond illumination device configured to move independent of saidcamera, image transmitting device, and said tip assembly.
 22. A methodof inspecting soldered connections between an IC and a circuit board,the method comprising: a disposing a circuit board having at least oneIC soldered thereto on a work surface of an inspection device; aligninga tip of the inspection device with a row of soldered connections to beinspected; illuminating the soldered connections to be inspected;visually examining the soldered connections between the IC and thecircuit board through an aperture disposed upon the tip of theinspection device; pivoting the tip assembly about an optical centerlineof said reflective device to view the upper or lower solder connections;rotating said tip assembly through about 180 degrees to view the sidesof the soldered connections; and visually inspecting the gaps formedbetween the soldered connections for optical clarity.
 23. The methodaccording to claim 20, wherein the step of illuminating furthercomprises using a second illuminating device to illuminate the solderedconnections from a direction opposite to the image receiving aperture.